Field of the Invention
The preferred embodiments are directed to industrial drives of industrial equipment and, more particularly, to a hydraulic PTO (power take-off) that can provide a dynamic braking action to large rotating components of industrial machines for reducing rotational speed of corresponding large inertial loads.
Discussion of the Related Art
Industrial equipment like industrial chippers, shredders, grinders, and crushers having large rotating components that are driven with robust industrial drives. Suitable industrial drives include hydraulic PTOs with hydraulic clutches that selectively connect and disconnect power between the driven industrial equipment and prime movers. Some hydraulic PTOs have internal brake assemblies for stopping and holding the large rotating components of the industrial equipment.
For simplicity and reliability in most applications, each internal brake assembly of a hydraulic PTO typically has a single clutch plate with a single braking surface. Single plate brake assemblies are limited in their use for stopping large rotating components of industrial equipment. That is because the large rotating components have enough mass to establish large inertial loads, which present numerous challenges while trying to actively brake, especially with single plate brake assemblies. Actively braking the large rotating components creates substantial heat in brake assemblies, potentially creating over-heating issues. Instead of actively braking, heat-induced issues in brake assemblies are avoided by allowing the rotating components to coast down to slow speeds before using the brake assemblies for slow speed final-stopping and holding or parking-type brake applications. Some rotating components are allowed to coast down to about 40 RPM (rotations per minute) or less before performing the brake application that performs the slow speed final-stopping. This coast-down process can take several minutes or more, during which time no servicing or other procedures can be performed on the industrial equipment.
Overall, a hydraulic PTO for use in an industrial drive of a piece of industrial equipment that allows for active braking of large rotating components of the industrial equipment to reducing stopping time was desired.